Postgresql 中文操作指南

ALTER OPERATOR

ALTER OPERATOR — 更改运算符的定义

ALTER OPERATOR — change the definition of an operator

Synopsis

ALTER OPERATOR name ( { left_type | NONE } , right_type )
    OWNER TO { new_owner | CURRENT_ROLE | CURRENT_USER | SESSION_USER }

ALTER OPERATOR name ( { left_type | NONE } , right_type )
    SET SCHEMA new_schema

ALTER OPERATOR name ( { left_type | NONE } , right_type )
    SET ( {  RESTRICT = { res_proc | NONE }
           | JOIN = { join_proc | NONE }
         } [, ... ] )

Description

ALTER OPERATOR 更改运算符的定义。

ALTER OPERATOR changes the definition of an operator.

您必须拥有该运算符才能使用 ALTER OPERATOR 。要更改所有者，您必须能够将其 SET ROLE 给新拥有者角色，并且该角色必须在运算符的架构上拥有 CREATE 权限。（这些限制强制更改所有者不会执行您无法通过删除并重新创建运算符来完成的操作。但是，超级用户无论如何都可以更改任何运算符的所有权。）

You must own the operator to use ALTER OPERATOR. To alter the owner, you must be able to SET ROLE to the new owning role, and that role must have CREATE privilege on the operator’s schema. (These restrictions enforce that altering the owner doesn’t do anything you couldn’t do by dropping and recreating the operator. However, a superuser can alter ownership of any operator anyway.)

Parameters

name
- The name (optionally schema-qualified) of an existing operator.
left_type
- The data type of the operator’s left operand; write NONE if the operator has no left operand.
right_type
- The data type of the operator’s right operand.
new_owner
- The new owner of the operator.
new_schema
- The new schema for the operator.
res_proc
- The restriction selectivity estimator function for this operator; write NONE to remove existing selectivity estimator.
join_proc
- The join selectivity estimator function for this operator; write NONE to remove existing selectivity estimator.

Examples

更改类型 text 的自定义运算符 a @@ b 的所有者：

Change the owner of a custom operator a @@ b for type text:

ALTER OPERATOR @@ (text, text) OWNER TO joe;

更改类型 int[] 的自定义运算符 a && b 的限制和连接选择性估计器功能：

Change the restriction and join selectivity estimator functions of a custom operator a && b for type int[]:

ALTER OPERATOR && (_int4, _int4) SET (RESTRICT = _int_contsel, JOIN = _int_contjoinsel);

Compatibility

SQL 标准中没有 ALTER OPERATOR 语句。

There is no ALTER OPERATOR statement in the SQL standard.